Encapsulated plastic panel and method of making the same

ABSTRACT

An economical method of manufacturing a plastic glazing panel having an encapsulation for aesthetic purposes and to enhance the sealing of the glazing panel to the vehicle is presented. This economical method includes the steps of forming forming a plastic panel having an A-side and B-side; printing an opaque border from an ink with the border being in contact with the B-side of the panel and substantially encircling the perimeter of the panel; curing the ink of the opaque border; applying a weatherable layer on the printed border and the plastic panel; curing the weatherable layer; depositing an abrasion resistant layer on the weatherable layer; placing the plastic panel into a mold having a soft gasket; injecting an elastomeric material to form an encapsulation that substantially encircles the perimeter of the plastic panel and encompasses the A-side; B-side and edge of the plastic panel; and removing the plastic panel from the mold.

This application claims the benefit of U.S. Provisional Application Ser.No. 60/915,274 filed on May 1, 2007, entitled “ENCAPSULATED PLASTICWINDOW,” the entire contents of which are incorporated herein byreference.

FIELD

This invention relates to plastic glazing panels that are encapsulatedto promote sealing and appearance when used as a window or sunroof.

BACKGROUND

For a number of years, car manufacturers have favored windowencapsulation for the sealing of automotive glass. Such encapsulationtechnology includes molding an elastomeric gasket directly onto thesurface of the glass. These gaskets are typically made from a variety ofmaterials including thermoplastic elastomers (TPE) and polyvinylchloride (PVC), as well as cross-linked polyurethanes applied viareaction injection molding (RIM). The encapsulation process for aconventional glass window may be described as including the steps ofapplying a primer or adhesion promoter to the perimeter of the one sideof the window; applying heat to this side of the window to activate theprimer; placing the window in a mold; injecting the thermoplasticelastomer onto the primer and the adjacent surface of the window;removing the window from the mold, and trimming any excess elastomericmaterial that has accumulated at the interface between the window andthe encapsulation. Such excess or scrap elastomeric material is known byone skilled-in-the-art of encapsulation as “flash” material. Thetrimming of the “flash” material is typically done with a sharp object,such as a knife or razor blade. The encapsulated glass window is thenfixed into the opening of a vehicle typically through the use of anadhesive system, such as the urethane BETASEAL™ system offered by DowAutomotive, Auburn Hills, Mich.

The use of plastic glazing panels provides several issues for the use ofconventional encapsulation technology. First, plastic glazing panels aretypically coated with a weatherable coating system, such as the acrylicprimer (e.g., SHP401 and SHP470) and silicone hard-coat (e.g., AS4000and AS4700) systems offered by Momentive Performance Materials, Wilton,Conn. in order for the glazing panel to survive exposure to theenvironment. Unfortunately the surface properties associated with asilicone hard-coat is such that most conventional encapsulationmaterials can not effectively adhere, thereby, creating a weakenedinterface that will cause the plastic glazing after being fixed to avehicle to prematurely fail. The known remedy for this situation hasbeen to apply the encapsulation to the bare plastic panel (e.g., noprotective coatings). However, this solution requires a masking stepbefore applying the weatherable coating and a de-masking step after theweatherable coating is cured. The addition of these two steps increasesthe costs associated with manufacturing an encapsulated plastic glazingpanel.

Second, plastic glazing systems are not as hard as a conventional glasswindow. Thus the trimming of any “flash” material created by theencapsulation process will result in irreversible damage to the coatingsystem of the plastic glazing panel. This damage will ultimately resultin premature degradation of the properties exhibited by the plasticglazing panel.

Finally, plastic glazing panels exhibit different thermal expansioncharacteristics than glass windows. Thus heating the surface of theplastic glazing panel to activate any adhesion promoter used tofacilitate adhesion between the plastic glazing panel and theencapsulation will cause substantial distortion to the shape of thewindow. Such a distortion will result in the operator having difficultyin securing the window into the mold during the encapsulation process.Thus this process will suffer from an increase in cycle time and anoverall loss in productivity.

Therefore, there is a need in the industry to develop a plastic glazingpanel and a process in which the plastic glazing panel can beencapsulated without degrading the properties exhibited by the plasticglazing panel or affecting cycle time or productivity.

SUMMARY

An economical method of manufacturing a plastic glazing panel having anencapsulation for aesthetic purposes and to enhance the sealing of theglazing panel to the vehicle is presented. This economical methodincludes the steps of forming a plastic panel having an A-side andB-side; printing an opaque border from an ink with the border being incontact with the B-side of the panel and substantially encircling theperimeter of the panel; curing the ink of the opaque border; applying aweatherable layer on the printed border and the plastic panel; curingthe weatherable layer; depositing an abrasion resistant layer on theweatherable layer; placing the plastic panel into a mold having a softgasket; injecting an elastomeric material to form an encapsulation thatsubstantially encircles the perimeter of the plastic panel andencompasses the A-side, B-side, and edge of the plastic panel; andfinally removing the plastic panel from the mold. The use of a softgasket in the mold reduces or eliminates the occurrence of “flash”material being generated at the edge of the interface between theencapsulation and the plastic glazing panel.

Optionally the step of applying an adhesion promoter on top of theabrasion resistant layer encircling the B-side perimeter of the plasticpanel may take place prior to placing the plastic panel into the mold toform the encapsulation. The plastic panel is then heated on the A-sideand B-side of the plastic panel in close temporal proximity to activatethe adhesion promoter without substantially distorting the shape of thewindow.

In another embodiment of the present invention, the steps of printing anopaque border from an ink and curing the ink on the plastic panel isreplaced with the steps of printing an opaque border from an ink on to aplastic film; curing the ink on the plastic film; and forming andadhering the opaque border and the plastic film to the B-side of theplastic panel so that the opaque border substantially encircles theperimeter of the plastic panel.

In another embodiment of the present invention the encapsulated plasticglazing panel comprises a substantially transparent plastic panel havingan A-side, B-side, and an edge; an opaque border in contact with theB-side of the plastic panel and that substantially encircles theperimeter of the plastic panel; a weatherable layer in contact with theopaque border and the plastic panel; an abrasion resistant layer incontact with the weatherable layer; and an encapsulation in contact withthe abrasion resistant layer and that substantially encircles theperimeter of the plastic panel and encompasses the A-side, B-side, andedge of the plastic panel.

In another embodiment of the present invention, the plastic glazingpanel further comprises a plastic film that has one side of the film incontact with the opaque border and the B-side of the plastic panel andthe other side of the film in contact with the weatherable layer.

In another embodiment of the present invention, the weatherable layermay include a single layer or multiple layers, such as a primer and atopcoat. The weatherable layer uses ultraviolet absorbing (UVA)molecules to protect the plastic panel from UV radiation.

In another embodiment of the present invention, the abrasion resistantlayer is deposited using a vacuum deposition technique. One example ofan abrasion resistant layer includes, but is not limited to, siliconoxy-carbide having a composition ranging from SiO_(x) toSiO_(x)C_(y)H_(z).

Further areas of applicability will become apparent from the descriptionprovided herein. It should be understood that the description andspecific examples are intended for purposes of illustration only and arenot intended to limit the scope of the present disclosure.

BRIEF DESCRIPTION OF THE DRAWINGS

The drawings described herein are for illustration purposes only and arenot intended to limit the scope of the present disclosure in any way.

FIG. 1 is a depiction of an automobile window according to theprinciples of the present invention.

FIG. 2 is a schematic of a manufacturing process for a plastic glazingpanel according to one embodiment of the present invention.

FIG. 3 is a diagrammatic representation of a cross-section of a glazingpanel from FIG. 1 according to one embodiment of the present invention.

DETAILED DESCRIPTION

The following description is merely exemplary in nature and is in no wayintended to limit the present disclosure or its application or uses. Itshould be understood that throughout the description and drawings,corresponding reference numerals indicate like or corresponding partsand features.

The present invention provides a plastic glazing panel and an economicalmethod of manufacturing such a glazing panel that includes theapplication of encapsulation that substantially encircles the perimeterof the window. The plastic glazing panel also includes a decorativeprinted border and a protective coating system to provide a high levelof weatherability and abrasion resistance. Referring to FIG. 1, aplastic glazing panel may be used as an automotive fixed side window 10.The window 10 is shown having a substantially transparent viewing area15, a printed opaque border 20 encompassing the transparent viewing area15, and an encapsulation 25 encircling the perimeter of the glazingpanel 10. One skilled-in-the-art of automotive design will realize thatthe plastic glazing panel of the present invention can be used for otherautomotive windows, such as a backlite, sunroof, and movable sidewindows, among others.

Referring to FIG. 2, an economical manufacturing process may generallybe defined by first forming 30 a plastic panel; then printing 35 anopaque border with an ink on the plastic panel; followed by curing 40the printed ink; applying 45 a weatherable layer onto the printedplastic panel; curing 50 the weatherable layer, depositing 55 anabrasion resistant layer onto the weatherable layer, placing 60 thepanel into a mold; forming 65 the encapsulation by injecting anencapsulating material to the outer perimeter of the glazing panel, andthen removing 70 the encapsulated glazing panel from the mold.

The transparent plastic panel may be formed 30 into a window, e.g.,vehicle window, from plastic pellets or sheets through the use of anyknown technique to those skilled in the art, such as extrusion, molding,which includes injection molding, blow molding, and compression molding,or thermoforming, which includes thermal forming, vacuum forming, andcold forming. It is to be noted that the forming 30 of a window usingplastic sheet may occur prior to printing as shown in FIG. 2, afterprinting 35 and curing 40 of the ink, or after application 45 and curing50 of the weatherable coating without falling beyond the scope or spiritof the present invention. The use of plastic pellets to form 30 theplastic panel is done prior to printing 35 the opaque pattern.

An opaque border may be defined as a substantially opaque ink printed orapplied 35 for decorative purposes and/or to hide or mask other vehiclecomponents (e.g., adhesives). This opaque border may be applied 35 tothe periphery of the transparent substrate to form a solid maskingborder. The opaque border may further include a fade-out pattern totransition the border into the viewing region of the window. Thefade-out pattern may incorporate a variety of shapes of variable sizeincluding dots, rectangles (lines), squares, and triangles, amongothers.

In one embodiment of the present invention, the opaque border and can beprinted 35 onto the surface of the plastic panel via screen printing.Other known methods of printing 35 the opaque border on the plasticpanel may also be utilized when deemed appropriate. A non-inclusive listof other known printing methods include pad printing, membrane imagetransfer printing, cylindrical printing, digital printing, roboticdispensing, mask/spray, ink-jet printing, and the like. The thickness ofthe printed ink may range from about 2 micrometers to about 1 mil (25.4micrometers) with about 6 to 12 micrometers being preferred.

Once the ink is printed 35, drying or curing 40 should be thorough inorder to ensure that any retained solvent is removed from the print. Theinks may be thermally cured by being exposed to an elevated temperaturefor a period of time, cured upon exposure to UV radiation, or via acombination thereof. The thickness of the cured ink print is typicallyabout 4 μm to 20 μm with between about 6 μm to 18 μm being preferred.

The weatherable layer is applied 45 to the printed panel by dip coating,flow coating, spray coating, curtain coating, spin coating, or any othertechniques known to those skilled-in-the-art. The thickness of theweatherable layer may range from about 2 micrometers to several mils (1mil=25.4 micrometers), with about 6 micrometers to 1 mil beingpreferred. The weatherable layer may then be cured 50 using a mechanismselected as one of air drying, UV absorption, thermal absorption,condensation addition, thermally driven entanglement, cross-linkinginduced by cationic or anionic species, or a combination thereof.

The weatherable layer is over-coated via the deposition 55 of anabrasion resistant layer. This abrasion resistant layer may be eithercomprised of one layer or a combination of multiple inter-layers ofvariable composition. The abrasion resistant layer is applied by anyvacuum deposition technique known to those skilled-in-the-art, includingbut not limited to plasma-enhanced chemical vapor deposition (PECVD),expanding thermal plasma PECVD, plasma polymerization, photochemicalvapor deposition, ion beam deposition, ion plating deposition, cathodicarc deposition, sputtering, evaporation, hollow-cathode activateddeposition, magnetron activated deposition, activated reactiveevaporation, thermal chemical vapor deposition, and any known sol-gelcoating process.

In one embodiment of the present invention, a specific type of PECVDprocess used to deposit the abrasion resistant layers comprising anexpanding thermal plasma reactor is preferred. This specific process(called hereafter as an expanding thermal plasma PECVD process) isdescribed in detail in U.S. patent application Ser. No. 10/881,949(filed Jun. 28, 2004) and U.S. patent application Ser. No. 11/075,343(filed Mar. 8, 2005), the entirety of both being hereby incorporated byreference. In an expanding thermal plasma PECVD process, a plasma isgenerated via applying a direct-current (DC) voltage to a cathode thatarcs to a corresponding anode plate in an inert gas environment. Thepressure near the cathode is typically higher than about 150 Torr, e.g.,close to atmospheric pressure, while the pressure near the anoderesembles the process pressure established in the plasma treatmentchamber of about 20 mTorr to about 100 mTorr. The near atmosphericthermal plasma then supersonically expands into the plasma treatmentchamber.

The reactive reagent for the expanding thermal plasma PECVD process maycomprise, for example, octamethylcyclotetrasiloxane (D4),tetramethyldisiloxane (TMDSO), hexamethyldisiloxane (HMDSO), vinyl-D4 oranother volatile organosilicon compound. The organosilicon compounds areoxidized, decomposed, and polymerized in the arc plasma depositionequipment, typically in the presence of oxygen and an inert carrier gas,such as argon, to form an abrasion resistant layer.

The plastic glazing panel is then placed 60 into a mold whose cavity isformed to the shape of the glazing panel. The mold is equipped with asoft gasket to seal the substantially transparent viewing portion of theglazing panel from the subsequent injection of the encapsulationmaterial that forms 65 the encapsulation. The gasket provides aneffective stop to the flow of the encapsulation material, thereby,eliminating the formation of any “flash” material at the edge of theinterface between the encapsulation and the glazing panel. The existenceof “flash” material is found to cause the formation of wrinkles orblemishes in the abrasion resistant layer of the plastic glazing. Inaddition, the trimming or removal of “flash” material via the use of asharp instrument, such as a knife or razor blade, can damage theabrasion resistant layer and the weatherable layer of the plasticglazing panel, as well as possibly the opaque border and the underlyingplastic panel itself.

Prior to placing 60 the plastic glazing panel into the mold, an adhesionpromoter may optionally be used to enhance adhesion between the abrasionresistant layer and the encapsulation. However, the conventional meansof applying and curing or activating the primer is unacceptable for usewith a plastic glazing system. The thermal expansion characteristics ofa plastic glazing panel are such that applying heat onto one surface ofthe plastic panel results in reversible expansion or distortion of theshape of the panel. This expansion or distortion results in difficultyin holding the glazing panel by any mechanical means (e.g., robotic,etc.) and in placing 60 the glazing panel into the mold. The applicationof heat on both surfaces of the glazing panel via substantiallysimultaneous application is found to minimize or eliminate theoccurrence of this distortion. The application of heat to both sides ofthe window may be accomplished through the use of any means known to oneskilled-in-the-art, including, but not limited to, IR heating or forcedair heating.

Referring now to FIG. 3, a cross-section of a plastic glazing panelaccording to one embodiment of the present invention is shown. Theplastic panel 15 may be comprised of any thermoplastic or thermosetpolymeric resin. The polymeric resins include, but are not limited to,polycarbonate, acrylic, polyarylate, polyester, and polysulfone, as wellas copolymers and mixtures thereof. In order to function appropriatelyas a window and to allow for the dual curing of the printed ink, theplastic panel 15 is substantially transparent.

The printed ink 20 may be comprised of a thermally curable ink or a UVcurable ink. A thermally curable ink may include a polyester-basedbinder, a polycarbonate-based binder, or a mixture thereof. A UV curableink may include a mixture of various multifunctional acrylate oligomersand monomers along with a photoinitiator. Examples of inks includeExatec® PIX (Exatec LLC, Wixom, Mich.) and DXT-1599 (Coates Screen, St.Charles, Ill.), among others.

The ink 20 may further comprise other additives, such as colorants(e.g., pigments and/or dyes), fillers, surfactants, defoamers,tackifiers, adhesion promoters, viscosity promoters, weatherabilityadditives. Examples of pigments include, but are not limited to, carbonblack, colored organic pigments, and metal oxide pigments; whilesuitable dyes include various direct dyes, acidic dyes, basic dyes,and/or reactive dyes. Various surfactants and defoamers may include anyorganic, organosilicon, and silicone molecules that are well known toone skilled-in-the-art to function in such a capacity. In order toenhance the weatherability of the printed and cured ink, the ink mayinclude hindered amines or UV absorber molecules.

The weatherable layer 75 may be comprised of, but not limited to,silicones, polyurethanes, acrylics, polyesters, polyurethane-acrylates,and epoxies, as well as mixtures or copolymers thereof. The weatherablelayer 75 preferably includes ultraviolet (UV) absorbing molecules, suchas hydroxyphenyltriazine, hydroxybenzophenones,hydroxylphenylbenzotriazoles, hydroxyphenyltriazines,polyaroylresorcinols,2-(3-triethoxysilylpropyl)-4,6-dibenzoylresorcinol) (SDBR),4,6-dibenzoylresorcinol (DBR), and cyanoacrylates, among others toprotect the underlying plastic panel and printed ink from degradationcaused by exposure to the outdoor environment.

The weatherable layer 75 may be comprised of one homogenous layer ormultiple sub-layers, such as a primer and a topcoat. A primer typicallyaids in adhering the topcoat to the plastic panel. The primer forexample may include, but not be limited to, acrylics, polyesters,epoxies, and copolymers and mixtures thereof. Similarly, the topcoat mayinclude, but not be limited to, polymethylmethacrylate, polyvinylidenefluoride, polyvinylfluoride, polypropylene, polyethylene, polyurethane,silicone, polymethacrylate, polyurethane-acrylates, polyacrylate,polyvinylidene fluoride, silicone hardcoat, and mixtures or copolymersthereof. One specific example of a weatherable layer 75 comprisingmultiple sub-layers is the combination of an acrylic primer (SHP401 orSHP470, Momentive Performance Materials, Waterford, N.Y.; or SHP-9X,Exatec LLC, Wixom, Mich.) with a silicone hard-coat (AS4000 or AS4700,Momentive Performance Materials; or SHX, Exatec LLC).

A variety of additives may be added to the weatherable layer 75, e.g.,to either or both the primer and the topcoat, such as colorants (tints),Theological control agents, mold release agents, antioxidants, and IRabsorbing or reflecting pigments, among others. The type of additive andthe amount of each additive is determined by the performance required bythe plastic glazing panel to meet the specification and requirements foruse as a window.

The abrasion resistant layer 80 may be comprised of aluminum oxide,barium fluoride, boron nitride, hafnium oxide, lanthanum fluoride,magnesium fluoride, magnesium oxide, scandium oxide, silicon monoxide,silicon dioxide, silicon nitride, silicon oxy-nitride, siliconoxy-carbide, hydrogenated silicon oxy-carbide, silicon carbide, tantalumoxide, titanium oxide, tin oxide, indium tin oxide, yttrium oxide, zincoxide, zinc selenide, zinc sulfide, zirconium oxide, zirconium titanate,or a mixture or blend thereof. Preferably, the abrasion resistant layer80 is comprised of a composition ranging from SiO_(x) toSiO_(x)C_(y)H_(z) depending upon the amount of carbon and hydrogen atomsthat remain in the deposited layer. This preferred silicon oxy-carbidelayer provides the surface properties suitable for the subsequentadherence of an encapsulation material.

The encapsulation 25 may be comprised of any known encapsulationmaterial known to one skilled-in-the-art including, but not limited to,polyvinyl chloride (PVC), thermoplastic elastomers, urethanes, andthermoplastic olefins. Optionally an adhesion promoter 85 may be used toenhance the adhesion between the encapsulation and the abrasionresistant layer. Examples of such adhesion promoters include acrylicpolymers, urethanes, organosilanes, and chlorinated polyolefin polymers,among others.

The encapsulated glazing panel may be fixed or secured to an opening ina vehicle through any means known to one skilled-in-the-art. Such meansinclude, but are not limited to, the use of clips or fasteners andbonding via the use of adhesives.

Before an encapsulated glazing panel can be used on a vehicle, theglazing panel must pass a series of tests specified by the originalequipment manufacturers (OEMs) to be done using either the finished,encapsulated plastic glazing panels or smaller test plaques or couponsthat represent the encapsulated glazing panel. One very demanding seriesof tests used with coupons is specified by Honda Motor Company asspecification number N/K. In this test, coupons of the encapsulatedglazing system are exposed to various conditions and then theencapsulation is pulled away from the plastic glazing panel under bothshear and peel loads. In order to pass each test in this series oftests, the failure mode observed upon separation of the encapsulationfrom the glazing panel must be 100% cohesive failure of theencapsulation. Any loss of adhesion at any interface within the plasticglazing panel (e.g., between the plastic panel and the ink, the ink andweatherable layer, or weatherable layer and abrasion resistant layer) orbetween the glazing panel and the encapsulation would constitute afailure.

An example of a standard set of tests performed on finished,encapsulated glazing panels is specified by General Motors as testspecification number GM-3611. Similar to the coupon testing, the fullglazing panels in this series of tests are exposed to various conditionsand the cohesive strength of the encapsulation evaluated by performingboth peel- and shear-oriented pull tests. In order to pass each test inthis series, the failure mode observed for the separation of theencapsulation and plastic glazing panel must be 100% cohesive failure ofthe encapsulation. Any loss of adhesion at any interface within theplastic glazing panel or between the glazing panel and encapsulationwould constitute a failure. The actual conditions to which fullencapsulated glazing panels and test coupons are exposed are shown inTables 1 and 2, respectfully.

The following specific examples are given to illustrate the inventionand should not be construed to limit the scope of the invention.

EXAMPLE 1 Testing of Encapsulated Plastic Glazing Panels

Multiple plastic glazing panels were formed using Lexan® polycarbonatesheet (SABIC Innovative Plastics, Pittsfield, Mass.) to fit a GeneralMotor's Trailblazer SUV as a fixed side window. The formed plastic panelwas printed with an opaque border using a thermally curable ink (Exatec®PIX, Exatec LLC, Wixom, Mich.), which was subsequently cured accordingto the manufacturer's specification. A weatherable layer comprised of anacrylic primer (SHP401, Momentive Performance Materials, Waterford,N.Y.) and a silicon hard-coat (SHX, Exatec LLC) was applied over theopaque border and plastic panel. On top of the weatherable layer, asilicon oxy-carbide abrasion resistant layer was deposited usingexpanding arc plasma enhanced chemical vapor deposition. The resultingplastic glazing panel is known as the Exatec® 500 glazing system (ExatecLLC, Wixom, Mich.).

An adhesion promoter was then applied around the perimeter of theglazing panel in-line with the opaque border. The adhesion promoter wascured or activated by simultaneously heating both sides of the glazingpanel using an IR heating source. The glazing panel was placed into amold and polyvinyl chloride (Vi-Chem Corporation, Grand Rapids, Mich.)injected to form the encapsulation.

The encapsulated plastic glazing panels were then tested according toGeneral Motors' GM-3611 specification. As shown in Table 1, theencapsulated glazing panels were observed to pass all of the testslisted in this specification by resulting in 100% cohesive failure ofthe PVC encapsulation. This example demonstrates that an encapsulatedplastic glazing panel prepared according to one embodiment of thepresent invention can pass stringent OEM requirements for use as awindow in a vehicle.

TABLE 1 Test Result Exposure Conditions _((Pass = 100% cohesive))Initial Pull Ambient Temperature PASS Humidity Resistance 38° C., 100%relative PASS humidity for 7 days Heat Resistance 70° C. for 14 daysPASS Thermal Cycle C Heat, humidity, Cold PASS cycling for 8 weeks

EXAMPLE 2 Testing of Encapsulated Glazing Coupons

Multiple plastic glazing coupons were formed using Lexan® polycarbonatesheet (SABIC Innovative Plastics, Pittsfield, Mass.) to be substantiallyflat. The formed plastic coupons were printed with an opaque borderusing a thermally curable ink (Exatec® PIX, Exatec LLC, Wixom, Mich.),which was subsequently cured according to the manufacturer'sspecification. A weatherable layer comprised of an acrylic primer(SHP401, Momentive Performance Materials, Waterford, N.Y.) and a siliconhard-coat (SHX, Exatec LLC) was applied over the each opaque border andplastic coupon. On top of the weatherable layer, a silicon oxy-carbideabrasion resistant layer was deposited using expanding arc plasmaenhanced chemical vapor deposition. The resulting plastic glazingcoupons represented a glazing system known as the Exatec® 500 glazingsystem (Exatec LLC, Wixom, Mich.).

An adhesion promoter was then applied around the perimeter of eachglazing coupon in-line with the opaque border. The adhesion promoter wascured or activated by simultaneously heating both sides of the glazingcoupons. The glazing coupons were placed into a mold and polyvinylchloride (Vi-Chem Corporation, Grand Rapids, Mich.) injected to form theencapsulation.

The encapsulated plastic glazing coupons were then tested according toHonda Motor Company's N/K specification. As shown in Table 2, theencapsulated glazing coupons were observed to pass all of the testslisted in this specification by resulting in 100% cohesive failure ofthe PVC encapsulation. This example demonstrates that an encapsulatedplastic glazing panel prepared according to one embodiment of thepresent invention can pass stringent OEM requirements for use as awindow in a vehicle.

TABLE 2 Test Result Exposure Conditions _((Pass = 100% cohesive))Initial Pull Ambient Temperature PASS Humidity Resistance 50° C., 95%relative PASS humidity for 90 days Heat Resistance 90° C. for 90 daysPASS Thermal Cycle C Heat, humidity, Cold PASS cycling for 8 weeks HotWater Resistance 80° C. for 100 hours PASS Hot Pull Test at 90° C. PASSCold Pull Test at −40° C. PASS Cataplasma Per IES60.014 protocol PASSXenon Arc 2000 hours per SAE PASS J1960 protocol

EXAMPLE 3 Adhesion Differences in Weatherable and Abrasion ResistantLayers

Multiple plastic glazing panels were formed using Lexan® polycarbonatesheet (SABIC Innovative Plastics, Pittsfield, Mass.) into asubstantially flat panel. The formed plastic panel was printed with anopaque border using a thermally curable ink (Exatec® PIX, Exatec LLC,Wixom, Mich.), which was subsequently cured according to themanufacturer's specification. A weatherable layer comprised of anacrylic primer (SHP-9×, Exatec LLC, Wixom, Mich.) and a siliconhard-coat (SHX, Exatec LLC) was applied over the opaque border andplastic panel. On about one-half of the panels, a silicon oxy-carbideabrasion resistant layer was deposited using expanding arc plasmaenhanced chemical vapor deposition. The resulting plastic glazing panelis known as the Exatec® 900 glazing system (Exatec LLC, Wixom, Mich.).The glazing panels having the outer layer as the weatherable layer(e.g., no deposited abrasion resistant layer) is representative of thesituation of the outer surface being a silicon hard-coat.

Adhesion promoters and a urethane adhesive bead was applied to theperimeter of the glazing panels having a silicon hard-coat surface andthe glazing panels having an outer surface of an abrasion resistantlayer. The adhesion promoters and urethane adhesive is known as theBETASEAL™ system offered by Dow Automotive, Auburn Hills, Mich. Theadhesion promoters and urethane adhesive was cured according to themanufacturer's specification.

The glazing panels were then subjected to a Cataplasma test known to oneskilled-in-the-art as Dow Automotive AG, Test Method No. 039E—CataplasmaTreatment. The Cataplasma test is also incorporated as one of the testsperformed in the Honda Motor Company N/K test specification. TheCataplasma test exposes the plastic glazing panel along with curedadhesive beads applied to the surface of the glazing panel to highhumidity at an elevated temperature followed by a low temperature shock(i.e., wrapping the glazing panel for 7 days in wet cotton at 70° C.followed by 3 hrs at −20° C.). Upon completion of the testing, and afterbeing equilibrated at room temperature (about 23° C.) the adhesive beadis pulled on each test panel and the degree of cohesive failure of theadhesive is examined. In order for a printed plastic glazing panel topass the Cataplasma test, there must be greater than 75% cohesivefailure of the adhesive. Therefore, for the plastic glazing panel topass the above test, the entire glazing panel, i.e., plastic panel15/cured ink 20/cured weatherable layer 75/abrasion resistant layer 80(if present) must exhibit a high level of hydrolytic stability atdifferent temperatures and moisture conditions.

The inventors observed that the plastic glazing panels have a siliconhard-coat outer surface in contact with the adhesion promoters andurethane failed the test with less than about 2% cohesive failure of theurethane. Rather poor adhesion between the silicon hard-coat and theadhesion promoters and urethane caused the failure. On the other hand,all samples tested that incorporated an outer surface of the abrasionresistant layer were found to pass the test with greater than 75%cohesive failure of the urethane. This example demonstrates thedifference in performance between a silicon hard-coat surface and thesurface of the abrasion resistant layer. Similar results are obtainablewhen the adhesion promoters and urethane are replaced with similaradhesion promoters and an encapsulation.

A person skilled in the art will recognize from the previous descriptionthat modifications and changes can be made to the present disclosurewithout departing from the scope of the disclosure as defined in thefollowing claims. A person skilled in the art will further recognizethat the various measurements and tests described are standardmeasurements that can be obtained by a variety of different testmethods. The test methods described in the examples represents only oneavailable method to obtain each of the required measurements.

1. A plastic glazing panel for use as an automotive window or sunroof,the glazing panel comprising: a substantially transparent plastic panelhaving an A-side, B-side, and an edge; an opaque border in contact withthe B-side of the plastic panel and that substantially encircles theperimeter of the plastic panel; a weatherable layer in contact with theopaque border and the plastic panel; an abrasion resistant layer incontact with the weatherable layer; and an encapsulation in contact withthe abrasion resistant layer and that substantially encircles theperimeter of the plastic panel.
 2. The plastic glazing panel of claim 1,wherein the encapsulation encompasses the A-side, B-side, and edge ofthe plastic panel.
 3. The plastic glazing panel of claim 1, wherein theencapsulation is one selected from the group of polyvinyl chloride(PVC), thermoplastic elastomers, urethanes, and thermoplastic olefins.4. The plastic glazing panel of claim 1, further comprising a plasticfilm in contact with the opaque border and the B-side of the plasticpanel.
 5. The plastic glazing panel of claim 4, wherein the plastic filmis in contact with the weatherable layer.
 6. The plastic glazing panelof claim 1, wherein the plastic panel is made from a thermoplastic orthermoset polymeric resin.
 7. The plastic glazing panel of claim 6,wherein the polymeric resin is one selected from polycarbonate, acrylic,polyarylate, polyester, polysulfone, and a copolymer or mixture thereof.8. The plastic glazing panel of claim 1, wherein the opaque border is anink that includes a binder selected as one from a polyester-based,polycarbonate-based, and acrylate-based binder.
 9. The plastic glazingpanel of claim 1, wherein the weatherable layer is one selected fromsilicones, polyurethanes, acrylics, polyesters, epoxies, and a copolymeror mixture thereof.
 10. The plastic glazing panel of claim 9, whereinthe weatherable layer uses ultraviolet absorbing (UVA) molecules toprotect the plastic panel from UV radiation.
 11. The plastic glazingpanel of claim 9, wherein the weatherable layer is made up of a primerand a topcoat.
 12. The plastic glazing panel of claim 1, wherein theabrasion resistant layer is one selected from aluminum oxide, bariumfluoride, boron nitride, hafnium oxide, lanthanum fluoride, magnesiumfluoride, magnesium oxide, scandium oxide, silicon monoxide, silicondioxide, silicon nitride, silicon oxy-nitride, silicon oxy-carbide,hydrogenated silicon oxy-carbide, silicon carbide, tantalum oxide,titanium oxide, tin oxide, indium tin oxide, yttrium oxide, zinc oxide,zinc selenide, zinc sulfide, zirconium oxide, zirconium titanate, and amixture or blend thereof.
 13. The plastic glazing panel of claim 12,wherein the silicon oxy-carbide abrasion resistant layer has acomposition ranging from SiO_(x) to SiO_(x)C_(y)H_(z).
 14. A method ofmanufacturing a plastic glazing panel for use as an automotive window orsunroof, the method comprising the steps of: forming a plastic panelhaving an A-side and B-side; printing an opaque border from an ink withthe border being in contact with the B-side of the panel andsubstantially encircling the perimeter of the panel; curing the ink ofthe opaque border; applying a weatherable layer on the printed borderand the plastic panel; curing the weatherable layer; depositing anabrasion resistant layer on the weatherable layer; placing the plasticpanel into a mold having a soft gasket; injecting an elastomericmaterial to form an encapsulation that substantially encircles theperimeter of the plastic panel; and removing the plastic panel from themold.
 15. The method of manufacturing a plastic glazing panel of claim14, wherein the step of injecting an elastomeric material forms anencapsulation that encompasses the A-side, B-side, and edge of theplastic panel.
 16. The method of manufacturing a plastic glazing panelof claim 14, further comprising the step of applying an adhesionpromoter on top of the abrasion resistant layer encircling the B-sideperimeter of the plastic panel prior to placing the plastic panel intothe mold to form the encapsulation.
 17. The method of manufacturing aplastic glazing panel of claim 16, further comprising the step ofheating the plastic panel on the A-side and B-side of the plastic panelin close temporal proximity to activate the adhesion promoter withoutsubstantially distorting the shape of the window.
 18. A method ofmanufacturing the plastic glazing panel of claim 14, wherein the step offorming the plastic includes a method selected from injection molding,blow molding, compression molding, thermal forming, vacuum forming, andcold forming.
 19. A method of manufacturing the plastic glazing panel ofclaim 14, wherein the ink printing step includes a method selected fromscreen printing, pad printing, or ink jet printing.
 20. A method ofmanufacturing the plastic glazing panel of claim 14, wherein the inkcuring step uses a method selected as one of air drying, UV absorption,thermal absorption, condensation addition, thermally drivenentanglement, cross-linking induced by cationic or anionic species, or acombination thereof
 21. A method of manufacturing the plastic glazingpanel of claim 14, wherein the step of applying the weatherable layeruses a method selected as one of flow coating, spray coating, curtaincoating, dip coating, or spin coating.
 22. A method of manufacturing aplastic glazing panel of claim 14, wherein the step of curing theweatherable layer includes a mechanism selected as one of air drying, UVabsorption, thermal absorption, condensation addition, thermally drivenentanglement, cross-linking induced by cationic or anionic species, anda combination thereof.
 23. A method of manufacturing the plastic glazingpanel of claim 14, wherein the step of depositing an abrasion resistantlayer uses a vacuum deposition technique.
 24. A method of manufacturingthe plastic glazing panel of claim 22, wherein the step of depositing anabrasion resistant layer uses a vacuum deposition technique selectedfrom plasma-enhanced chemical vapor deposition (PECVD), expandingthermal plasma PECVD, plasma polymerization, photochemical vapordeposition, ion beam deposition, ion plating deposition, cathodic arcdeposition, sputtering, evaporation, hollow-cathode activateddeposition, magnetron activated deposition, activated reactiveevaporation, thermal chemical vapor deposition, and any known sol-gelcoating process.
 25. A method of manufacturing the plastic glazing panelof claim 14, wherein the steps of printing an opaque border from an inkand curing the ink on the plastic panel is replaced with the steps ofprinting an opaque border from an ink on to a plastic film; curing theink on the plastic film; and forming and adhering the opaque border andthe plastic film to the B-side of the plastic panel so that the opaqueborder substantially encircles the perimeter of the plastic panel.